Solidor Tower (in French tour Solidor) is a strengthened keep with three linked towers, located in the estuary of the river Rance in Brittany.
It was built between 1369 and 1382 by John V, Duke of Brittany (i.e. Jean IV in French) to control access to the Rance at a time when the city of Saint-Malo did not recognize his authority. Over the centuries the tower lost its military interest and became a jail. It is now a museum celebrating Breton sailors exploring Cape Horn.
The Solidor tower is located in the former city of Saint-Servan, which merged with Saint-Malo in 1967.
It is featured in the 1956 Wendy Toye film True as a Turtle starring John Gregson, Cecil Parker, June Thorburn and Keith Michell http://www.imdb.com/title/tt0049886/.
Brittany (French: Bretagne [bʁətaɲ] ( listen); Breton: Breizh, pronounced [brɛjs]; Gallo: Bertaèyn) is a cultural region in the north-west of France. Previously a kingdom and then a duchy, Brittany was united to the Kingdom of France in 1532 as a province. Brittany has also been referred to as Less, Lesser or Little Britain (as opposed to Great Britain). It is characterised as one of the six Celtic nations.
Brittany occupies a large peninsula in the north west of France, lying between the English Channel to the north and the Bay of Biscay to the south. Its land area is 34,023 km² (13,136 sq mi). The historical province of Brittany is divided into five departments: Finistère in the west, Côtes-d'Armor in the north, Ille-et-Vilaine in the north east, Loire-Atlantique in the south east and Morbihan in the south on the Bay of Biscay.